MATLAB: How to convert all vector elemens into zeros but not the maximum and the minimum of it

indexindexingvectorvectorizationvectors

Hey

How to turn v into zeros and just keep the maximum and the minimum alement?

% Generate v
n=[1,5];
v=unifrnd(-1, 5, n);
% Remove Direct Dublications
v = v([true, diff(v)~=0]);

Best Answer

Try this modification

Related Solutions

MATLAB: Speed up indexing without using a loop

Maybe logical indexing is faster:

N; % given nx1 matrix with some values
D = inf(n,1);
D(1,1) = 0;
M = false(n,1);
while ~all(M)
  D_adj = D;
  D_adj(M) = inf; % or any very large number
  [~, index_m] = min(D_adj);
  M(index_m) = true;
  FOR LOOP % another code for a FOR loop to update values in matrix D;
end

Remember the golden rule of optimizing code: Use the profiler at first to find the bottleneck of the function. If you accelerate a part of the by a factor 2, but this part needs 2% of the processing time, the total speedup is 1% only.

I doubt, that this indexing is the bottleneck of your code. But logical indexing should be at least faster.

I guess, that the part hidden behind "FOR LOOP" can be improved such, that the new minimal value can be found by a cheaper method.

MATLAB: How can i account for the last variable of a vector while comparing the n and (n+1) variables

You can keep it from over-writing the vector by having it take the minimum of the ‘(i+1)’ index and the number of elements in the vector, as ‘min((i+1),numel(v))’:

v=fix(rand(1,10)*201-100);
V1=v;
for i=1:10
    if rem(v(i),2)==0
        if rem(v(min(i+1,numel(v))),2)==1   % Replace ‘(i+1)’ With ‘numel(v)’ If ‘(i+1)’ Over-Writes The Vector
            v(i)=v(i+1);
        else
            v(i)=v(i);
        end
    end
    v2(1,i)=v(i);
end
disp(V1)
disp(v2)

See if that does what you want.

I am not certain what you are doing, so you may need to experiment with this idea to get the result you want.

Best Answer

Related Solutions

MATLAB: Speed up indexing without using a loop

MATLAB: How can i account for the last variable of a vector while comparing the n and (n+1) variables

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